Sleep Health and Obstructive Sleep Apnea Risk in Portuguese Firefighters: Preliminary Baseline Findings From a Prospective Cohort

Background and objective Firefighters face irregular schedules, night operations, and fragmented sleep, placing them at risk of sleep disorders and operational fatigue. Despite growing international evidence, sleep health data on Portuguese firefighters are scarce. In this study, we aimed to report baseline findings from the Associação Chama Saúde Initiative, a nationwide prospective cohort designed to characterize sleep health, obstructive sleep apnea (OSA) risk, and diagnostic yield within a structured screening-to-diagnosis framework, as well as the operational sleep context among Portuguese firefighters. Methods Active-duty firefighters completed a structured baseline online questionnaire (n=1815), including demographic data, medical history, lifestyle factors, the Epworth Sleepiness Scale (ESS), the STOP-Bang questionnaire, and operational sleep variables. Participants screening with high risk of OSA proceeded to home sleep testing (HST) and Pulmonology referral. Outcomes included descriptive screening metrics, the feasibility of the diagnostic cascade, and early treatment uptake. Results The mean age distribution was skewed toward 30-49 years (63.4%), and 75% were male. BMI categorization indicated that 69% of participants were overweight or obese. Cardiovascular comorbidities were reported in 19%, and previous mental health diagnoses in 24%. Excessive daytime sleepiness (ESS >10) was present in 589 participants (32%). STOP-Bang identified a high OSA risk in 377 participants (21%). Operational sleep restriction was pronounced, with 59% reporting ≤4 hours of sleep during service, compared with 92% reporting ≥5 hours off duty. A structured diagnostic cascade was feasible at the national scale: 1815 participants were screened, 603 screened positive, 370 underwent HST, 228 were diagnosed with OSA, and 77 initiated continuous positive airway pressure (CPAP)/auto-adjusting positive airway pressure (APAP) treatment. Conclusions Preliminary baseline data indicate a substantial burden of sleep-related symptoms and elevated OSA risk among Portuguese firefighters, compounded by operational sleep restriction. Nationwide diagnostic implementation proved feasible, with early treatment uptake observed. Longitudinal follow-up will assess clinical outcomes and treatment adherence.